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SSX MHD plasma wind tunnel

Part of: Experiments Fundamental Plasma Physics

Published online by Cambridge University Press:  17 March 2015

Michael R. Brown  and
David A. Schaffner Open the ORCID record for David A. Schaffner [Opens in a new window]
Michael R. Brown*
Affiliation:
Department of Physics and Astronomy, Swarthmore College, 500 College Ave. Swarthmore, PA 19081, USA
David A. Schaffner
Affiliation:
Department of Physics and Astronomy, Swarthmore College, 500 College Ave. Swarthmore, PA 19081, USA
*
†Email address for correspondence: doc@swarthmore.edu
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Abstract

A new turbulent plasma source at the Swarthmore Spheromak Experiment (SSX) facility is described. The MHD wind tunnel configuration employs a magnetized plasma gun to inject high-beta plasma into a large, well-instrumented, vacuum drift region. This provides unique laboratory conditions approaching that in the solar wind: there is no applied background magnetic field in the drift region and has no net axial magnetic flux; the plasma flow speed is on the order of the local sound speed (M ~ 1), so flow energy density is comparable to thermal energy density; and the ratio of thermal to magnetic pressure is of order unity (plasma β ~ 1) so thermal energy density is also comparable to magnetic energy density. Results presented here and referenced within demonstrate the new capabilities and show how the new platform is proving useful for fundamental plasma turbulence studies.

Type
Research Article
Information
Journal of Plasma Physics , Volume 81 , Issue 3 , June 2015 , 345810302
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Copyright
Copyright © Cambridge University Press 2015 

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